1. Field of the Invention
The present invention relates to the marking of soft tissue specimens to preserve or reconstruct the orientation of a soft tissue specimen after the specimen is removed from the patient's body.
2. Description of the Related Art
The marking of a biopsy specimen to indicate the orientation of the specimen within the body may be crucial for later treatment. For example, knowledge of the exact orientation of a biopsy specimen of breast tissue is an important aspect of any breast conserving therapy for breast cancer. A proper biopsy should have good margins of normal, uninvolved breast tissue surrounding the cancerous lesion within the breast. If a margin is “dirty” (close to or involved with the lesion), the risk of recurrence of the cancer increases. What distance actually constitutes a good margin remains controversial. Large margins are safest, but may result in an overly large cavity within the breast, which may result in a less than satisfactory cosmetic result. Smaller margins, on the other hand, result in smaller cavities within the breast, but increase the risk that some of the cells on the periphery of the margin will be found to be involved in the lesion. Moreover, smaller margins may increase the risk of seeding cancerous cells within the breast. For example, 1 cm margins are universally accepted as safe, while some favor the excision of specimens with margins of as little as 1 mm. The National Surgical Adjuvant Breast and Bowel Project (NSABP), the major study group for breast treatment, has previously endorsed a margin equal to one normal cell between the cancer and the cut edge of the specimen. The mainstream approach, however, appears to call for 5 mm to 10 mm margins between the cancerous lesion and the cut edge of the specimen. Except for some women with Ductal Carcinoma In Situ (DCIS), women who undergo biopsies with such margins will also receive post-operative radiation therapy to treat any remaining cancer within the breast.
Best practices indicate that the biopsy specimen should be marked after removal thereof form the patient, in case one or more cut surfaces contain tumor or are close to the tumor. If the surgeon learns from the pathologist that the inferior margin is “positive”, the he or she will take the patient back to the operating room and excise additional tissue from the inferior aspect of the cavity. If the specimen is not adequately marked, then tissue from the entire cavity must be excised. This may lead to the unnecessary excision of a vast amount of normal breast tissue, leading to an unsatisfactory cosmetic result. For at least these reasons, specimen marking for orientation is essential and should be an integral part of any breast (or any other soft tissue) cancer treatment protocol.
Many surgeons mark the excised specimen by sewing a suture onto different sides of the specimen (usually two or three sides). An example of such marking would be a short suture to mark the superior aspect of the specimen, a long suture to mark the lateral aspect thereof and a suture with short and long tails to mark the deep aspect of the specimen. If the surgeon determines that a radiograph or an X-ray is needed to confirm that the excised specimen contains suspicious microcalcifications, the specimen may be sent to a radiology department before the pathologist receives the specimen. The specimen is then typically flattened between two parallel plates to take the radiograph. This completely distorts the specimen, and it will never return to its original shape. This distortion renders the reconstruction of the specimen orientation difficult. For example, after a flattened specimen is returned to the surgeon, the sutures for the superior and lateral aspects may appear on the same side of the specimen.
A second and better way to mark specimens is to mark each side of the excised specimen (6 sides total) with a different color of stain. In this manner, if the specimen is distorted following a radiograph, the colored stain will still dictate the original orientation of the excised specimen within the surrounding tissue.
When a tissue specimen is removed from the breast, it should be removed without disturbing its original orientation within the breast. However, during the actual excision when the specimen is still within the breast, it may twist and/or turn, which changes its orientation even before it is removed. Thus, marking a specimen after removing it from the patient may not preserve the original orientation of the specimen. Therefore, even conscientious marking of an excised specimen may not preserve the true orientation of the lesion within the surrounding tissue. In turn, such marking may lead to confusion, misinformation and ultimately may result in a less than optimal treatment of the patient.
What are needed, therefore, are improved methods and systems for tissue marking. What are also needed are methods, systems and devices for preserving the orientation of tissue specimens.